Re: [PATCH RESEND 2/2] ring-buffer/selftest: Handle meta-page bigger than the system
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2024-09-10 16:45:55
Also in:
linux-kselftest, lkml
Shuah, Can you take this through your tree? Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> -- Steve On Tue, 10 Sep 2024 17:23:35 +0100 Vincent Donnefort [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Handle the case where the meta-page content is bigger than the system page-size. This prepares the ground for extending features covered by the meta-page. Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: linux-kselftest@vger.kernel.org Signed-off-by: Vincent Donnefort <redacted>diff --git a/tools/testing/selftests/ring-buffer/map_test.c b/tools/testing/selftests/ring-buffer/map_test.c index ba12fd31de87..d10a847130fb 100644 --- a/tools/testing/selftests/ring-buffer/map_test.c +++ b/tools/testing/selftests/ring-buffer/map_test.c@@ -92,12 +92,22 @@ int tracefs_cpu_map(struct tracefs_cpu_map_desc *desc, int cpu) if (desc->cpu_fd < 0) return -ENODEV; +again: map = mmap(NULL, page_size, PROT_READ, MAP_SHARED, desc->cpu_fd, 0); if (map == MAP_FAILED) return -errno; desc->meta = (struct trace_buffer_meta *)map; + /* the meta-page is bigger than the original mapping */ + if (page_size < desc->meta->meta_struct_len) { + int meta_page_size = desc->meta->meta_page_size; + + munmap(desc->meta, page_size); + page_size = meta_page_size; + goto again; + } + return 0; }